基于体积特性的钢渣沥青混合料最佳油石比等体积设计方法研究

Research on Equal-volum e D esign M ethod of Optim al Oil-to-Rock Ratio of SteelSlag AsphaltM ixtures Based on Volum e Characteristics

为了建立一种将玄武岩沥青混合料最佳油石比转化为钢渣沥青混合料最佳油石比的设计方法,首先,采用等体积替换法得到钢渣的实际用量;随后,采用CT扫描技术研究了钢渣集料多孔特性对沥青的多余吸附量,从而确定了钢渣的吸附机理,并建立了一种钢渣集料的材料组成设计方法。研究结果表明:粒径为10~15 mm的钢渣集料表面孔内沥青体积占钢渣集料表面实际沥青体积的20.21%;粒径为5~10 mm的钢渣集料表面孔内沥青体积占钢渣集料表面实际沥青体积的6.70%。基于体积特性的材料组成设计方法计算的钢渣沥青混合料最佳油石比为5.79%,与马歇尔击实试验结果基本一致。现场检测结果表明,5.70%油石比摊铺的钢渣沥青路面具有优异的抗滑性能和路用价值,对保障路面行车安全具有突出意义。与玄武岩沥青路面相比,钢渣沥青路面的摆值和横向力系数多分布于数值较高的区域,其具有更加优异的抗滑性能。

In order to establish a design method for converting the optimal oil-to-rock ratio of basalt asphalt mixture into the optimal oil-to-rock ratio of steel slag asphalt mixture,firstly,the actual amount of steel slag is obtained by the equivalent volume substitution method;Subsequently,CT scanning technology was used to study the excess adsorption volume of asphalt on the porous properties of steel slag aggregates to determine the adsorption mechanism and establish a material composition design method for steel slag aggregates.The research results show that the volume of asphalt in the pores of steel slag aggregate with a particle size of 10~15 mm accounts for 20.21% of the actual asphalt volume on the surface of steel slag aggregate,and the same one with a particle size of 5~10 mm accounts for6.70%.Based on volume characteristics,the optimal oil-to-rock ratio of steel slag asphalt mixture calculated by the material composition design method is 5.79%,which is basically consistent with the results of Marshall compaction test.The on-site inspection results show that the steel slag asphalt pavement with a 5.70% oil-to-rock ratio has excellent anti-skid performance and road value,which is of outstanding significance for road driving safety.Compared with basalt asphalt pavement,the swing value and lateral force coefficient of steel slag asphalt pavement are more distributed in areas with higher values with better anti-skid performance.